Method of and apparatus for making narrowed knitwear on flat-bed knitting machines

ABSTRACT

A METHOD OF MAKING NARROWED KNITWEAR ON A FLAT BED KNITTING MACHINE IN WHICH THE ENTIRE NARROWING OPERATION TAKES PLACE DURING A RETARDED RETURN STROKE OF THE KNITTING CARRIAGE, AND NARROWING DEVICE FOR A FLAT-BED KNITTING MACHINE WITH A PLURALITY OF NARROWING HOUSING FIXEDLY MOUNTED ON THE THREAD GUIDE BRIDGE OF THE KNITTING MACHINE, GROOVED SHAFTS, CAM DISCS AND ECCENTRICS SLIDABLY AMOUNTED ON THE GROOVED SHAFTS, AND A DRIVE INCLUDING A SLIDE AND A SERIES OF CONNECTING LINKS FOR DRIVINGLY CONNECTING THE DISCS AND ECCENTRICS TO THE NARROWING NEEDLES IN THE NARROWING HOUSINGS FOR RESPECTIVELY LIFTING AND LOWERING AND LATERALLY OFFSETTING THE NEEDLE.

Oct. 5, 1971 lRMSCHER ETAL 3,609,996

METHOD OF AND APPARATUS FOR MAKING NARROWED KNITWEAR ON FLAT-BEDKNITTING MACHINES 3 Sheets-Sheet 1 Filed Dec. 17, 1968 FIG. 1

FIG. 4

\ ML INVENTORS HELMUT IRMSCHER HARALD KUHNRICH BY 7M6 724$ ATTORNEYSOct. 5, I971 METHOD OF AND APPARATUS FOR MAKING NARROWED KNITWEAR FiledDec. 17, 1968 H. IRMSCHER FIG. 3

ET AL ON FLAT-BED KNITTING MACHINES 3 Sheets-Sheet 5 O 29 ROTATEIQGNARROWING FING SHAFT NEEDLES 7 NARROWIN THREAD GUIDE KNTTING LEFT BRIDGETRANSPORT mc NEEDLES PUNCHED CLUTCH NARROWING TAPE SHAFT NEEDLES READERCLUTCH I ECCENTRIC 5 25 1235 NARROWING- ROTATING INVENTORS CONDENSERR'GHT F'NGER HELMUT IRMSCHER I THREAD GUIDE HARALD KUHNRICH CARRIAGEBRIDGE TRANSPORT REVERSAET BY R N DECELE 0 7714a 77 52 ATTORNEYS3,609,996 METHOD OF AND APPARATUS FOR MAKING NARROWED KNITWEAR ONFLAT-BED KNIT- TING MACHINES Helmut Irmscher and Harald Kuhnrich,Karl-Marx-Stadt,

Germany, assignors to VEB Fahrradwerk Elite- Diamant, Karl-Marx-Stadt,Germany Filed Dec. 17, 1968, Ser. No. 784,411 Int. Cl. D04b 7/10 US. C].66-70 Claims ABSTRACT OF THE DISCLOSURE A method of making narrowedknitwear on a flat bed knitting machine in which the entire narrowingoperation takes place during a retarded return stroke of the knittingcarriage, and a narrowing device' for a flat-bed knitting machine with aplurality of narrowing housings fixedly mounted on the thread guidebridge of the knitting machine, grooved shafts, cam discs and eccentricsslidably mounted on the grooved shafts, and a drive including a slideand a series of connecting links for drivingly connecting the discs andeccentrics to the narrowing needles in the narrowing housings forrespectively lifting and lowering and laterally offsetting the needle.

BACKGROUND OF THE INVENTION The present invention relates to a narrowingdevice and to a method of making narrowed knitwear on flatbed knittingmachines, and more particularly, to a device in which the narrowing iseffected by narrowing needles arranged in a so-called narrowing housing.

Flat-bed knitting machines are known in which a support carrying thenarrowing device is arranged aside from the feeder sled on the sledrails. The narrowing device is provided with a guide block and acorresponding guide groove or path on which a sled or carriage ismounted. The carriage in turn is equipped with a shaft carrying a gear,an intermediate gear, a rack and a guiding plate with a guiding railwhich carries a reciprocal member carrying the so-called narrowingshoes.

The movement of the narrowing shoes, the offsetting of the needle bedand the movement of the knitting needles during the narrowing processare effected by a shaft arranged transversely to the needle beds in theframe of the knitting machine, which shaft carries several fixedlyarranged cam discs. These cam discs are connected via linkages, anglelevers, racks etc. to the respective member to be moved. The drive ofthe above-mentioned shaft is effected by means of the main drive shaftof the knitting machine to which it is connected by a clutch andcontrolled by the master or pattern device. The various cam discs effectthe movement of the supports with the narrowing device, the advance andretraction of the knitting needles, the movement of the narrowingneedles, and the offsetting of the needle bed during the narrowingoperation.

As is apparent from the above, this narrowing device is extremelycomplicated and cumbersome. More specifically, the movement of thenarrowing shoes is only possible through the intervention of very manyintermediate members, such as shafts, gears, racks, and levers, in viewof the very unfavorable arrangement of the shaft with the cam discs inthe machine frame. Moreover, the needle bed has also to be offset duringthe narrowing operation. Therefore, the entire narrowing device is veryviable to breakdowns, a large material expense is necessary, and theexact adjustment and mounting of the various parts is difficult.Furthermore, with such a device it is only possible to narrow theknitwear on one side, and to narrow only very loose knitwear, in view ofthe employment of narrowing shoes.

There is furthermore known a narrowing device in which the narrowinghousing with the narrowing means and the control members for thelifting, lowering and offsetting of the narrowing means are displaceablyarranged on a guiding rail above the needle beds. In this instance, thecontrol curves or members for the lifting, lowering and offsetting ofthe narrowing means are located at the feeder carriage or an auxiliarycarriage. The lowering and lifting of the narrowing means during thenarrowing operation is effected by a corresponding movement of thenarrowing housing, and the offsetting is effected by a cam controlled,vertically reciprocable slide arranged at the carriage, which slideoffsets the housing during the narrowing operation by one needle pitcheach. The narrowing means are formed by narrowing shoes.

The disadvantage of this arrangement, however, consists in that itrequires for the narrowing housing a special guiding rail above theneedle bed, and in that in addition to control members for the lowering,lifting and offsetting of the narrowing shoes, special control discs orcams are required at the feeder carriage or auxiliary carriage, and inthat the narrowing housing has to be moved along during the entirenarrowing operation. Furthermore, with this arrangement of the narrowingdevice, a long and heavy carriage and thereby a large lost-motion andgreat power losses result. Since the narrowing operation is carried outduring the knitting operation, the narrowing can be carried out alwaysonly on one side of the knitwear and the knitting speed can only berelatively low. In view of the employment of narrowing shoes, only veryloose knitwear can be narrowed.

Furthermore, flat-bed knitting machines with a lateral loop transferdevice have become known, in which there is provided for each knittingneedle at the respective needle axis a narrowing needle having its ownsupport. Each narrowing tool consists of a coat or sleeve in which tworelatively displaceable sinkers and a narrowing needle (eyelet portionwith tiltable hook) are arranged. The one sinker displaces the narrowingneedle in the direction of the needle movement, whereas the other sinkerturns the hook-shaped end of the narrowing needle. For purposes ofoffsetting the narrowing tools, special offsetting sinkers are providedwhich are arranged on guiding plates provided with oblique slots throughwhich the offsetting sinkers are in engagement with the narrowing tools.The entire narrowing operation, including the offsetting operation, iscontrolled by separate systems mounted on the carriage. The narrowingoperation is carried out during the knitting.

In view of the provision of special needle beds for the narrowing tools,which needle beds have to be in exact alignment with the needle beds ofthe knitting needles, the narrowing device is easily subject todisturbances and failure. Moreover, an extremely precise assembly isnecessary. Special difficulties arise in connection with the lateraldisplacement of the narrowing tools due to the employment of offsettingsinkers, which frequently leads to a jamming of the sinkers and therebyto disturbances in the narrowing operation. Also this narrowing devicerequires an extremely complicated and solid, long carriage. As mentionedabove, the great lost motion of the carriage and thereby a considerablepower loss will result.

It is, therefore, an object of the present invention to provide anarrowing device and a method for producing narrowed knitwear, whichwill overcome the abovementioned disadvantages of the heretofore knownnarrowing devices and methods.

It is another object of the present invention to provide a narrowingdevice in which a minimum of elements and masses is to be moved; adevice which requires a minimum of material and assembly costs, whilepermitting the highest possible efiiciency in knitting.

A still further object of the invention consists in that the narrowinghousing and the arrangement of the narrowing housing in the flat bedknitting machine are such that they permit an accurate and fastexecution of the narrowing process.

Also, it is an object of the invention to provide a method for producingnarrowed knitwear which makes it possible to narrow the knitwearsimultaneously on both sides.

BRIEF SUMMARY OF THE INVENTION The narrowing device according to thepresent invention is characterized primarily in that the narrowinghousing is fixedly connected to the thread guide bridge of the knittingmachine and in that cam discs and lateral offsetting eccentrics areslidably arranged in narrowing housings on grooved shafts, said camdiscs and eccentrics being connected to the narrowing needles via aslide, connecting links and a connecting rod.

In accordance with the invention, the production of narrowed knitwear iseffected in such a way that the entire narrowing process including theoffsetting of the narrowing needles is carried out during the return ofthe carriage, during one revolution of the grooved shafts extendingthrough the narrowing housing with its slidably arranged cam discs andlateral offsetting eccentrics. The drive of the carriage is controlledin such a way that the same has a time period of reversal correspondingto the time period required for the narrowing process. After completionof the narrowing process, the narrowing housings are moved along by thecarriage of the knitting machine by one or more needle pitches in thedirection toward the center of the needle bed, depending on the numberof the narrowed loops.

The narrowing process is initiated by the control device of the knittingmachine via a clutch and a gear motor. The clutch connects the motorwith a transmission which cooperates with the eccentrics and groovedshafts controlling the movement of the knitting needles, so that asynchronous movement of the narrowing needles and the knitting needlesreleasing and receiving the loops of the knitwear, is effected. Thereturn of the thread guide bridge with the narrowing housing to itsstarting position is carried out by the carriage of the knitting machineby a clutch rendering ineffective the locking means of the thread guidebridge.

The invention will become more readily apparent from the followingdescription of a preferred embodiment thereof shown, by way of example,in the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a cross section through aneedle bed of a fiatbed knitting machine and through a narrowing deviceaccording to the present invention;

FIG. 2 is a section taken along the line IIII of FIG. 1;

FIG. 3 is an end view of a knitting machine with the narrowing deviceaccording to the invention;

FIG. 4 is a sectional view taken along line A-A in FIG. 2 showing anmore detail the clutch for unloading the bridge;

FIG. 5 is a section taken along the line V-V of FIG. 2;

FIG. 6 is a section taken along the line VIVI of FIG. 2; and

FIG. 7 diagrammatically illustrates the control sequence during thenarrowing process when carried out on the apparatus according to theinvention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to thedrawings in detail, the knitting machine illustrated in FIGS. 1, 2 and 3comprises two needle beds 1, 1, with knitting needles 2, 2 respectively,which are actuated during the narrowing operation through theintervention of push rods 3, 3', levers 4, 4' and eccentrics '5, 5. Thelevers 4, 4 are pressed against the eccentrics 5, 5' by springs 6, 6',respectively.

Narrowing needles 7, 7 in alignment with the knitting needles 2, 2'respectively, are arranged above the needle beds 1, 1, the narrowingneedles 7, 7' being provided in narrowing housings 8, 8 respectively.These housings 8, 8 are fixedly mounted on a thread guide bridge 9. Thisbridge 9 in turn is slidably mounted on thread guide rails 10, 10" whichare fixedly connected with the machine frame (not shown) of the knittingmachine. Bridge 9 is furthermore provided with a gear rack 11 which isslidably arranged in bearings 12 (see FIG. 2) and is drivingly connectedto a Geneva stop 13 via a gear 14. The Geneva stop 13 is driven throughthe intervention of an actuating disc 15 which is drivingly connected toan advancing wheel 34 via a transmission 33, and via a transmission 48,reversing wheel 45, and a transmission 47 with the advancing wheel 46.

In the following description reference is made to the showing of FIG. 2.It is to be kept in mind that this figure represents a cross sectionthrough one narrowing housing of one needle bed only and that anidentical narrowing housing is to be found on the opposite side of lineAA shown in FIG. 1.

A grooved shaft 16 with a key 17 extends through the narrowing housing 8in guiding means 39 and 40. Between one housing wall 37 of the twohousing walls 37, 38 and the guiding means 39, an offsetting eccentric18 is slidably mounted on the grooved shaft 16, whereas an offsettingeccentric 19 is arranged between the housing wall 38 and the guidingmeans 40. Furthermore, control discs 21, 25 and 26 are slidably mountedbetween the guiding means 39 and 40. As will be evident from FIG. 2, theguiding means 39 and 40 sit in walls 35 and 36 which together with aconnecting leg 41 form an inner housing. A slide 20 is arranged withinthis inner housin and is slidably journaled in guiding grooves of theWalls 35 and 36. A connecting rod 23 is rotatably connected to the slide20. The wall 35 has fixedly connected thereto a lever 27 which extendsthrough an oblong hole 22a of a connecting rod 22. The two connectingrods 22 and 23 are adapted to actuate a connecting link 24 which in turnhas connected thereto the narrowing needle 7. Slide 20, lever 27, aswell as the connecting rods 22 and 23 are pressed against the controldiscs 21, 25 and 26 by return spring 42.

OPERATION OF THE DEVICE The production of narrowed knitwear is effectedin the following manner. During the normal knitting operation, thecarriage 32 of the knitting machine is reciprocated in the customary,well-known manner. If the knitwear is to be narrowed, the control device30 consisting of a punched tape, punched tape reader and magnets issuescontrol commands. This is accomplished by the electro-magnets which areenergized in accordance with the predetermined program of the punchedtape. The punched tape is traced by the punched tape reader, one trackactuating the left pair of narrowing housings, the other actuating theright pair of narrowing housings. By punching the tape accordingly it ispossible to narrow symmetrically and asymmetrically. The narrowingprocess is being carried out while the carriage is at a standstill, inthe reverse. The deceleration of the reverse of the reversible motornecessary for this procedure is determined by the capacity of acondenser. During this time period of retarded or decelerated movementof the carriage, the control device 30 also initiates the connection ofa motor 28 to a transmission 31 via a clutch 29 to thereby actuate theeccentrics 5 and 5' and the shafts 16, 16' (keeping in mind that thearrangement is symmetrical to the line AA in FIG. 1). The knittingneedles 2, 2 are brought into a corresponding gripping position for thenarrowing needles 7, 7' through the intervention of the eccentrics 5,and the push rods 3, 3'. The actuation, i.e., rotation of the shaft 16(16') brings about the execution of the narrowing process. First, theslide 20 (and 20) is displaced in axial direction of the knittingneedles 2, 2' by means of the control disc 21 (21). In view of thecombination and the shape of the control discs 25, 26, 26) (see FIGS. 5and 6) the narrowing needles 7, 7 via the two rods 22, 23, (22, 23) thelever 27, (27') and the connecting link 24 (24') carry out a lifting andsimultaneously a rotative movement so that the eyelets of the narrowingneedles 7, 7' respectively move into the hook portions of the knittingneedles 2, 2. The narrowing needles 7, 7 take over the loops from theknitting needles 2, 2' and are lifted during the. further movement ofthe control discs 25 and 26 (2?, 26') in cooperation with the rods 22,23 (22', 23) and the connecting links 24, (24) above the combs 0f theneedle bed. In this position, the lateral offsetting of the narrowingneedles 7, 7 is effected by the offsetting eccentrics 18 and 19, (18 and19) depending on the design of the latter, by at least one needle pitch.

Upon further movement of the control discs 25, 26 (25, 26'), thenarrowing needles 7, 7' are lowered again and with their eyelets graspthe loop receiving knitting needles 2, 2. Subsequently, the narrowingneedles move upwardly again, release the knitting needles 2, 2' with thetransferred loops and return to their starting position in view of theaction of the lateral offsetting eccentrics 18, 19 (18, 19) and thecontrol discs 21 (21), the return of the members 20, 22, 23, 27, (20',22, 23, 27) being effected by return springs 42, 42. The narrowinghousing is not offset. The knitting needles, now without a loop, throughthe intervention of a rotating finger arranged at the feeder carriageare pressed out of the range of the feeder. The rotating fingers obtaintheir command for this action from the control device 30. The totaljust-described narrowing process takes place during one completerevolution of the grooved shaft 16 (16').

Following completion of the narrowing operation, the carriage 32 resumesits movement. During this movement the carriage actuates the Geneva stop13 by means of the transporting wheel 34 via the transmission 33, withits fixedly arranged actuating disc 15 and thereby also moves thenarrowing housing by one or more steps equalling one or more needlepitch. The advance of the narrow ing housing 8, 8 by the Geneva stop 13is always effected in the direction towards the center of the needlebed.

Upon completion of the knitwear, the thread guide bridge isautomatically transported by the sled or carriage towards the outside.The locking of the transport of the thread guide bridge by the Genevastop 13 is removed by a clutch (not shown) arranged on the shaft of theGeneva stop 13.

The description given above was concerned with a narrowing device on oneside of a pair of needle beds. It is possible to arrange the samedevice, including motor, clutches, etc. also on the other side of thepair of needle beds, as illustrated in FIG. 3. In this way, it ispossible to make narrowed knitwear either only on one side orsimultaneously on both sides of the needle bed. 'When making narrowedknitwear simultaneously on both sides of the needle bed the thread guidebridges with one stroke of the carriage can be switched simultaneouslyto the inside. This requires that one of the two bridges is moved in adirection opposite to the direction of the carriage. The switchingcounter to the direction of the carriage is effected by the reversingwheel 45, and the advancing wheel 46 together with the transmissiongears 47 and 48. The initiation of the narrowing process on both sidesis then likewise effected by the control device which simultaneouslyactuates both clutches 29.

Summarizing the invention, in view of the design and arrangement of thedevice in accordance with the invention, and the method explained above,the execution of the narrowing process is effected with a movement of aminimum of masses. The utilization of the thread guide bridge as asupport for the narrowing housings eliminates the heretofore necessaryand customary transport devices, such as spindles, and the like. Thedirect support of the narrowing tools at the location where they performtheir work, makes it possible to adjust the entire device precisely.Therefore, knitwear can be narrowed simultaneously on both sides and theactual knitting process can be carried out with normal, not reducedknitting speed.

While a preferred embodiment of the invention has been described inconnection with the accompanying drawings, it is to be understood thatthe scope of the invention is solely determined by the attachedapparatus and method claims.

What is claimed is:

1. In combination, a flat-bed knitting machine having needle bed means,a plurality of knitting needles mounted for reciprocation on the needlebed means, a yarn guide bridge mounted adjacent the needle bed means, aplurality of narrowing housings fixedly connected to said bridge, adrive shaft passing through said housings, in each of said housings afirst non-circular control disc mounted on said shaft for rotation withsaid shaft, a slide mounted for sliding in the axial direction of atleast some of the knitting needles, the first control disc being inengagement with the block so as to move the block in said axialdirection when the shaft is rotated, a second noncircular control discand a third non-circular control disc each mounted on the shaft forrotation with the shaft, two rods arranged on opposite sides of andoperatively connected to the block, bridging the rods a member carryingnarrowing needles, and means operatively connecting each of said secondand third non-circular control discs to a respective one of said armsfor rotating the narrowing needles as the shaft is rotated to move theslide.

2. The combination according to claim 1, wherein said knitting machinecomprises a knitting carriage, means for driving said carriage, controlmeans drivingly connecting said carriage driving means to said narrowinghousings for moving the latter by a distance corresponding to a desirednumber of spaces between adjacent needles toward the center of saidneedle bed means.

3. The combination according to claim 1, wherein said knitting machineincludes a clutch, a gear motor, and a transmission drivinglyinterconnected and cooperating with said non-circular control discs andsaid shafts for coordinating the synchronous movement of said knittingand narrowing needles.

4. The combination according to claim 1, which includes locking meansfor locking said bridge in a certain position, and clutch means forunlocking said locking means to thereby permit return of said bridge andnarrowing housings to their starting positions.

5. The combination of claim 1, further comprising a fourth and a fifthcontrol disc each mounted on the shaft for rotation therewith, each ofsaid fourth and fifth control discs having a non-planar surface, saidnon-planar surfaces being operatively connected to said opposite sidesof the block for periodically laterally offsetting the block andtherewith the narrowing needles upon rotation of the shaft.

References Cited UNITED STATES PATENTS 575,395 l/1897 Granz 667O3,220,220 11/ 1965 Imon 66-76 3,248,903 5/1966 Coppo 66-70 3,349,57610/1967 Borne 66-64 X FOREIGN PATENTS 1,408,516 7/1965 France 66-76RONALD FELDBAUM, Primary Examiner US. Cl. X.R. 66-76

